The product of my number and twice my number is 128 what is half my number

Let's call your number n. Twice your number is 2n. The product of your number and twice your number (so n multiplied by 2n) is 128.

Set up an equation:

n × 2n = 128

2n² = 128

Divide both sides by 2:

n² = 64

Square root both sides to isolate n:

n = 8

The question asks for half your number, so just half 8:

8 ÷ 2 = 4.

Half your number is 4.